Risk factors for gastrointestinal symptoms. The Danish Gulf War Study

Compared with controls, up to six years after their return, Danish Gulf War Veterans have a significantly higher prevalence of self-reported gastrointestinal symptoms characterized by constant or occasional recurrent diarrhoea and frequent rumbling of the stomach within the preceding 12 months. The aim of this study was to clarify whether these symptoms could be attributed to physical, chemical or biological exposures.

Some 686 subjects who had been deployed in the Persian Gulf within the period August 2 1990 until December 31 1997 were included in a prevalence study using retrospective data on exposure; the control group comprised 257 subjects matched according to age, gender and profession. All participants underwent clinical and paraclinical examinations, and were interviewed by a physician based on a previously completed questionnaire.

Among Gulf War Veterans the prevalence of gastrointestinal symptoms was 9.1% vs 1.7% among controls, p < 0.001. Of 24 physical, chemical or biological exposures, 15 were significantly, p < 0.05, associated with the outcome in bivariate analyses. After multivariate adjustment, two exposure variables were significantly associated with the outcome: Burning of waste or manure and exposure to insecticides against cockroaches; tooth brushing using water contaminated with chemicals or pesticides, and bathing in or drinking contaminated water, were nearly significant, p < 0.10. A group of 74 subjects had 3-4 of these exposures, and a prevalence of 18.9%; 164 subjects had 2 exposures and a prevalence of 12.8%, 270 subjects with one symptom had a prevalence of 7.4%, and 153 subjects without any of these exposures had a prevalence of 2.0%, a prevalence comparable to that of controls. The associations were not explained by differences in psychiatric symptoms, age or gender.

Our results suggest that, 1) a large proportion of long-term gastrointestinal problems among Gulf War Veterans can be attributed to specific exposures, 2) it should be possible to avoid a large proportion of long-term gastrointestinal symptoms in future similar missions by committed interventive measures.